1. Field
The present application relates generally to wireless communications, and more specifically to systems, methods, and devices for optimally phase rotating duplicate frames in wireless local area network (WLAN) transmissions. Certain aspects herein relate to determining phase rotations for use with frames which contain a number of identical frequency segments, such that the phase rotations will reduce the peak-to-average power ratio (PAPR) of the frame.
2. Background
In many telecommunication systems, communications networks are used to exchange messages among several interacting spatially-separated devices. Networks may be classified according to geographic scope, which could be, for example, a metropolitan area, a local area, or a personal area. Such networks would be designated respectively as a wide area network (WAN), metropolitan area network (MAN), local area network (LAN), or personal area network (PAN). Networks also differ according to the switching/routing technique used to interconnect the various network nodes and devices (e.g. circuit switching vs. packet switching), the type of physical media employed for transmission (e.g. wired vs. wireless), and the set of communication protocols used (e.g. Internet protocol suite, SONET (Synchronous Optical Networking), Ethernet, etc.).
Wireless networks are often preferred when the network elements are mobile and thus have dynamic connectivity needs, or if the network architecture is formed in an ad hoc, rather than fixed, topology. Wireless networks employ intangible physical media in an unguided propagation mode using electromagnetic waves in the radio, microwave, infra-red, optical, etc. frequency bands. Wireless networks advantageously facilitate user mobility and rapid field deployment when compared to fixed wired networks.
The devices in a wireless network may transmit/receive information between each other. The information may comprise packets, which in some aspects may be referred to as data units. In some types of wireless networks, it may be useful to transmit duplicate (DUP) frames, which contain a number of identical frequency segments. For example, a DUP frame may contain a plurality of identical frequency segments, such as containing a 1 MHz segment which is transmitted over 2, 4 or 8 MHz by duplicating the 1 MHz segment 2, 4 or 8 times to fill up that bandwidth.